The phase transition by crystallization and a grain growth behavior of a Zr 65 Cu 27.5 Al 7.5 metallic glass were examined as a function of isothermal annealing time at various temperatures. At the initial stage of crystallization, a metastable Zr(Al, Cu) phase is observed, in addition to a main phase of Zr 2 Cu, below the annealing temperature of 730K. The formation of Zr(Al, Cu) may be attributed to the strong chemical affinity between Al and Zr. The grain growth rate for Zr 2 Cu is extremely low comparing with that for a Zr 65 Cu 35 binary metallic glass. Therefore, the strong chemical affinity between Al and Zr seems to contribute to the retardation of nucleation and grain growth of the crystalline phases. The grain growth kinetics can be described by log(dD/dtg)=log(k/3)−2logD where D is the measured grain size, t g the grain growth time and k the constant. The activation energy Q for grain growth is calculated to be 165kJmol −1 .